Hypometric genetics: Improved power in genetic discovery by incorporating quality control flags

Tanigawa and Kellis. Am J Hum Genet. (2024).


Phenotype: Free Chol. to Tot. Lipids in CMs and XXL VLDL % (BLQ removed)

  • Estimated h2 in white British population in UKB: 0.055 (95% CI:[0.043, 0.066]).

Predictive performance of iPGS models

We evaluated the predictive performance of the inclusive polygenic score models using the held-out test set individuals.

Population
Model
PGS trait type
Metric
Predictive Performance
95% CI
P-value
Population Model PGS trait type Metric Predictive Performance 95% CI P-value
1 - 10 / 35 (35)
white BritishCovariate-only modelDerived (percentage traits, excl. BLQ measurements)R20.044[0.040, 0.048]8.0x10-286
white BritishGenotype-only modelBLQ (derived)R20.007[0.005, 0.008]2.8x10-44
white BritishGenotype-only modelDerived (percentage traits, incl. BLQ measurements)R20.041[0.037, 0.044]1.3x10-264
white BritishGenotype-only modelDerived (percentage traits, excl. BLQ measurements)R20.045[0.041, 0.049]4.7x10-296
white BritishFull model (covariates and genotypes)BLQ (derived)R20.011[0.009, 0.013]1.9x10-69
white BritishFull model (covariates and genotypes)Derived (percentage traits, incl. BLQ measurements)R20.082[0.077, 0.087]<1.0x10-300
white BritishFull model (covariates and genotypes)Derived (percentage traits, excl. BLQ measurements)R20.091[0.086, 0.096]<1.0x10-300
Non-British whiteCovariate-only modelDerived (percentage traits, excl. BLQ measurements)R20.034[0.016, 0.052]5.8x10-10
Non-British whiteGenotype-only modelBLQ (derived)R20.000[-0.002, 0.002]5.0x10-01
Non-British whiteGenotype-only modelDerived (percentage traits, incl. BLQ measurements)R20.016[0.003, 0.028]2.9x10-05

The predictive performance (R2), its 95% confidence interval (CI), and statistical significance (P-value) are shown for each population in UK Biobank in the held-out test set. The "model" column indicates whether the predictive performance is from the covariate-terms alone (covariate-only model), PGS terms alone (Genotype-only model), or the full model containing both PGS and covariate terms. We used the following sets of covariates in our analysis: age, sex, age2, age*sex, Townsend deprivation index, and genotype PCs (PC1-PC18). Please refer to our publication for a more detailed description of the methods.


Coefficients (BETA) of PGS models

/static/data/tanigawakellis2024/per_trait/INI10023582/pgscoeffs.png

We show the coefficients (BETA) of PGS models. Our iPGS model selected 2707 variants with non-zero coefficients. The genetic variants with the large absolute values of coefficients are annotated in the plot. There is no guarantee that our iPGS model selects causal variants. We use the GRCh37/hg19 reference genome.

The top 100 genetic variants with the largest absolute value of coefficients

CHROM
POS
Variant
Variant ID
Effect Allele
Consequence
Gene symbol
Effect Weight
CHROM POS Variant Variant ID Effect Allele Consequence Gene symbol Effect Weight
1 - 10 / 100 (100)
61610101186:161010118:A:Grs10455872GIntronicLPA0.409741482729792
61609611376:160961137:T:Crs3798220CPAVsLPA0.35870409697424
155872342615:58723426:A:Grs1077835GIntronicALDH1A2, LIPC0.281662226606316
176421058017:64210580:A:Crs1801689CPAVsAPOH0.140200025806681
61610173636:161017363:G:Ars73596816AIntronicLPA0.115988430770696
155867851215:58678512:C:Trs10468017TIntronicALDH1A20.100413643481753
224432472722:44324727:C:Grs738409GPAVsPNPLA30.0967988417631485
155868336615:58683366:A:Grs1532085GIntronicALDH1A2-0.0892635539508071
194541564019:45415640:G:Ars445925AOthersAPOC10.0882698677617636
61610060776:161006077:C:Trs41272114TPTVsLPA-0.079015983366555

There is no guarantee that our iPGS model selects causal variants. We show the top 100 variants with the largest effect size (BETA). To see 2707 variants included in our iPGS model, please download the iPGS coefficients by clicking the download button. We use the GRCh37/hg19 reference genome.


Follow-up analysis

There are several ways to use the resource in your research. First, you may use our iPGS coefficients and compute individual-level polygenic scores for your cohort. Second, you may also investigate the genetic variants with non-zero coefficients and their annotated genes to learn more about biology by taking advantage of the sparsity of our iPGS models. For your convenience, here we suggest several resources as an example of follow-up analysis. We do not intend to cover all the relevant follow-up analyses.

Using iPGS coefficients

By clicking the download button above, you may download the iPGS coefficients. Our FAQ page shows the description of file format and how you may use iPGS coefficients in your research.

HaploReg

HaploReg is a tool for exploring annotations of the non-coding genome at variants on haplotype blocks. The button above submits the top 100 genetic variants with the largest absolute value of coefficients as a query to HaploReg using the default parameters in HaploReg v4.2 (LD threshold r2 >= 1, ChromHMM 15-state model, SiPhy-omega, and GENCODE genes). HaploReg's ability to browse haplotypes is useful here as there is no guarantee that our iPGS model selects causal variants. The 'top 100 variant' cutoff is an arbitrary threshold; we aim to demonstrate how one may investigate the selected variants. Please check Ward and Kellis. Nucleic Acids Res. 2012 and Ward and Kellis. Nucleic Acids Res. 2016 for more information on HaploReg.


References